Selector switch means



Oct. 5, 1965 J. B. CATALDO ETAL 3,210,488

SELECTOR SWITCH MEANS Filed March 19, 1963 3 Sheets-Sheet 2 INVENTORS D Jay/v .9. 6/77/7106 PEA/VA: 1o. ,e z xsv All Oct. 5, 1965 J. a. CATALDO ET A].

SELECTOR SWITCH MEANS Filed March 19, 1965 3 Sheets-Sheet 3 United States Patent 3,210,488 SELECTOR SWITCH MEANS John B. Cataldo, Bloomfield Hills, Frank W. Kussy,

Birmingham, and Gus Witzmann, Detroit, Mich.,

assignors to I-T-E Circuit Breaker Company, Philadelphia, Pa., a corporation of Pennsylvania Filed Mar. 19, 1963, Ser. No. 266,265 23 Claims. (Cl. 200-50) The instant invention relates to motor starters in general and more particularly relates to means for selecting the mode of operation for the main interlock of the motor starter.

Motor starters of the type illustrated in copending application, Serial No. 189,915, filed April 24, 1962, in the name of J. B. Cataldo et al., entitled Electrical Device, assigned to the assignee of the instant invention, are provided with main interlocks for actuating and deactuating the motor starter. The main interlock is provided with a normally open switch in series with a normally closed switch, with each of the switches being operated by an individual depressible actuator. In order to actuate the motor starter the normally open switch is momentarily closed while to deactuate the motor started the normally closed switch is momentarily opened.

The instant invention provides novel means whereby the main interlock is selectively operated to achieve one of three modes of operation, namely, HAND, OFF, or AUTO. In the AUTO position, the normally open switch is open and the normally closed switch is closed; in the OFF position the normally open switch is open; and the normally closed switch is also open; while in the HAND position the normally open switch is closed and the normally closed switch is also closed. The switching means, or selector, for achieving these various modes of operation is a purely mechanical device which is usually mounted to the outside of the main interlock housing by simple screw means. For some applications the selector is mounted to the inside of an openable enclosure cover. The selector is an elongated member mounted to a guide bracket for linear motion. Cams carried by the selector are positioned to engage and operate appropriate contact actuators of the main interlock. The selector also carries a spring pressed detent rod which ispositioned to fall into notches of the guide bracket to thereby establish discreet positions for the selector.

For a selector mounted directly to the main interlock, means external to the enclosure for the motor starter are provided for operation of the selector. This means includes a rotary member extending through the enclosure cover to operate a crank on the inside of the cover. The crank is provided with an elongated notch which receives a portion of the selector so that the rotary motion may be converted into linear motion of the selector.

Accordingly, a primary object of this invention is to provide a selector means which may readily be added to a motor starter for determining the mode of operation of this motor starter main interlock with the selector construction being such that no electrical wiring changes ice able externally of the motor starter enclosure for operating a selector of this type.

Yet another object is to provide a purely mechanical selector which may be mounted directly to a starter or an enclosure.

These as well as further objects of this invention shall become readily apparent after reading the following description of the accompanying drawings in which:

FIGURE 1 is an end view of a motor starter showing the main interlock and the selector of the instant invention mounted thereto.

FIGURE 2 is a side elevation showing the relationship between the main interlock, the selector, and the cover carrying means for operating the selector.

FIGURE 3 is an end view looking in the direction of arrows 3-3 of FIGURE 2.

FIGURE 4 is a plan view looking in the direction of arrows 4-4 of FIGURE 2.

FIGURE 5 is an exploded perspective of the selector unit.

FIGURES 5A, 5B and 5C are electrical schematics showing the connections between the main interlock switches and the coil of the contactor. In FIGURE 5A the selector is in the HAND position, in 5B the selector is in the OFF position, while in 50 the selector is in the AUTO position. 7

FIGURE 6-is a perspective of the main interlock and a modified selector.

FIGURE 7 is a fragmentary side elevation of the main interlock and the cooperating mechanical element of the contactor.

Now referring to the figures. As clearly seen in FIG- URE 1 and as described in detail in the aforesaid copending application 189,915, main interlock 20 of motor starter 21 is mounted at one end of base 22 adjacent to contactor 23 with terminals 27 and 28 projecting from opposite ends of interlock housing 36. Screws 24 and 25 provide mechanical securement and electrical connections for main interlock 20. Screw 25 passes through an aperture in interlock terminal 26 and is received by threaded aperture in terminal 27 insulatingly carried by base 22 with terminal 27 being adapted for connection to a source of control power. Screw 24 passes through a clearance aperture in interlock terminal 28 and is received by a threaded aperture of terminal 29 insulatingly mounted to base 22. One end of contactor coil 30 is connected to terminal 27 while the other end is connected to an energizing source. V

Main interlock 20 further includes normally closed switch 31 and normally open switch 32 connected in series. Jumper 33 connecting switches 31 and 32, is provided with terminal 34 extending through a side aperture of housing 36 and adapted to be connected to an automatic device such as pressure switch or thermostatic switch connected by merely two wires in parallel with normally open switch 32. Depressible actuators 35 and 38 are guided for linear movement by suitable internal guide formations of housing 36. When actuator 35 is depressed blade 37 is moved downward to open normally closed switch 31 while downward movement of actuator 38 operates blade 39 downward thereby closing normally open switch 32.

As will be hereinafter explained, in the normal or AUTO operational mode (FIGURE 5C) normally closed switch 31 is closed and normally open switch 32 is open. In the OFF operational mode (FIGURE 5B) both switches 31 and 32 are open while in the HAND operational mode (FIGURE 5A) both switches 31 and 32 are closed. In order to operate main interlock 20 between these three operational modes a selector means is provided. It is noted that for operation with the selector means of this invention, there is no lost motion connection between the contact carrier of contactor 23 and actuator 38. This selector means is an assembly consisting of guide bracket 40 which carries selector 44 with the latter being journalled for linear movement with respect to the former.

Guide bracket 40 is an elongated plate-like member which is mounted to main interlock 20 by means of screws 41 and 42 extending into interlock housing 36 through clearance apertures in down-turned wings 98, 99, respectively, near each end of bracket 40. Bracket 40 so positioned that the main portion thereof is in spaced parallel relatioirto the top of main interlock housing 36.

Selector 44 :is a T-shaped member whose cross arm 45 is disposed below the main portion of guide bracket 40 with the leg 46 of selector 44 extending upwardly through longitudinal slot 40a of guide bracket 40. Leg, or handle, 46 is provided with a longitudinally extending recess- 47 wherein spring 48' is disposed. Detent pin 49 extends through recess 47 being biased downwardly by spring 48 into engagement with the top surface of the guide bracket 40. The top surface of the guide bracket 40 is provided with three depressions 51, 52, 53 extending perpendicular to the axis of slot 40:: on opposite sides thereof. Depressions 51-53 are positioned to receive the ends of detent pin 49 and cooperate therewith in establishing discreet positions for selector 44.

. The bottom surface of selector 4 is provided with cams 45 and 48 which are engageable with actuators 35 and 38, respectively, and when engaged are effective to depress the respective actuators. As is clearly seen in FIG- URE 2, with detent pin 49 in notch 52 cam 45 depresses actuator 35 thereby opening normally closed switch 31. In this same position it is seen that cam 48 is clear of actuator 38 so that normally open switch 32 is open. This is the OFF position illustrated in FIGURE B.

In like manner, with detent pin 49 in notch 53 carns 45 and 48 are clear of actuators 35 and 38 so that normally close-d switch 31 is in the closed position and normally open switch 32 is in the open position. This is the AUTO position of FIGURE 5A. Similarly, with detent pin 49 in notch 51 cam 45 is clear of actuator 35 and cam 48 depresses actuator 38 so that normally closed switch 31 is closed and normally open switch 32 is also closed. This is the HAND position of FIGURE 5A.

In operation, motor starter 21 is mounted within an enclosure wlth the front of starter 2 1 confronting enclosure wall 61 as seen in FIGURES 2 and 3. Quite often wall 61 is an opena'ble cover. Selector knob 62 is mounted on the outside of wall 61 and is journalled for rotative movement in knob holder 63 which lies against the outside surface of wall 61. Stub shaft 64 extends downwardly from knob 62 through aligned clearance apertures in holder 63 and wall 61, and through spacer '65 which lies adjacent to the inner surface of wall 61. The lower end of stub shaft 64 carries crank 66 which is secured in operative position by screw 67 which is received by a threaded aperture in the end of shaft 64. The end of crank 66 remote from shaft 65 is bifurcated to form a pair of spaced arms 66a, 66b between which selector leg 46 is disposed. This type of connection permits wide tolerances in the spacing between cover 61 and selector 44.

Spring 96 biases knob 62 to a central position wherein the space between arms 66a, 66b is aligned to receive leg 46 upon closing of cover 61 when detent pin 49 is in center notch 52. 'The back surfaces 67a, 67b of arms 66a, 66b, respectively, are sloped in opposite directions away from the central portion of crank 66.

When detent pin 49 is in either of the outer notches 51 or 53 and cover 61 is closed, one of the back surfaces 67a, 67b engages the sloping free end of leg 46 so that crank 66 is cammed, against the force of spring 96, to the appropriate side for leg 46 to enter the space between arms 66a and 66b.

The selector means herein'before described is illustrated 4 as being operable to only two positions because of removable blocking member (FIGURE 5). Member 80 is constructed of sheet material and consists of legs '82 and 83 at right angles to one another and a mounting leg 81 at right angles to both legs 82, 83.

Member 80 is mounted by passing screw 42 through aperture 84 in leg 81 so that leg 82 is positioned along the top surface of bracket 40 and leg 83 is positioned to block movement of selector 44 to the right with respect to FIGURE 2. Thus, pin 49 may only be moved between detent notches 51 and 52 wherein switches 31 and 32 are operated to the positions shown in FIGURES 5A and 5B, respectively.

The selector means of FIGURE 6 includes all of the constructional elements of the selector means previously described. In addition select-or means 140 is provided with extension extending downwardly from the back edge selector 144. Extension 145 extends to the bottom 147 of notch 146 in the back of the main interlock housing at the top thereof. The width of notch 146 is 'sufiicient .to permit free travel of extension 145 as selector 144 is operated between its extreme positions.

Notch 146 also provides clearance for the travel of pin 130 (FIGURE 6) which mechanically engages handle 38 of main interlock 20 for holding contacts 39 closed when contactor 23 is closed. Pin 130 is provided with threads 131 for mounting pin 130 to one leg of bracket 132. The other leg of bracket 132 is secured by fastening means 133 to the movable contact carrier 134 of con tactor 23. The mechanical engagement between the contactor and main interlock is fully described in the aforesaid copending application Serial No. 189,915.

When a selector means is used this mechanical connection between the contactor and main interlock must not be present.

As clearly seen in FIGURE 7, it is a simple matter to dismount threaded pin 130 from cont-act bracket 132 thereby severing the mechanical connection between main interlock 20 and movable contact carrier 134.

Extension 145 cooperates with notch 146 to assure that this mechanical connection is severe-d before selector means can be properly mounted to interlock 20. That is, with pin 130 present, even with pin 130 resting against the bottom 147 of notch 146, pin 130 will be engaged by selector extension 145. When such engagement takes place apertures 98 and 99 in the front legs of bracket 40 cannot be aligned with the threaded apertures of main interlock 20 which receive mountingscrew 41, 42. Extension 145 is of suflicient width that it will interfere with pin 130 for all positions of selector 144.

Thus, this invention provides a novel construction for a motor starter selector switch which may be installed without the necessity of making any electrical connection and only requires minimal simple mechanical connection.

Although we have described preferred embodiments of our novel invention, many variations and modifications will now be obvious to those skilled in the art, and We prefer therefore to be limited not by the specific disclosure herein but only by the appended claims.

The embodiments of the invention in which an excluiive privilege or property is claimed are defined as folows:

1. In combination an interlock unit, a contactor operating coil, and a selector device; said unit including a first normally open switch and a second normally closed switch serially connected and connected in series with said coil, a housing wherein said switches are disposed, first and second actuators extending externally of said housing for operating said first and second switches, respectively; said selector device comprising a mounting member, a selector carried by said member and movable with respect thereto, and means defining discreet first, second, and third positions for said selector relative to said member; means movably mounting said selector device in opera tive position relative to said" interlock unit; said selector 5 when in said first position operating said first actuator to close said first switch; said selector when in said second position operating said second actuator to open said second switch.

2. The combination of claim 1 also including a removably mounted element positioned to prevent operation of the selector to said third position.

3. The combination of claim 1 in which the selector is provided with a first cam and a second cam, said first cam operating said first actuator when said selector is in said first position and said second cam operating said secnd actuator when said selector is in said second position.

4. The combination of claim 1 in which the mounting member includes a plate portion, said selector including a main portion and a handle portion, said main portion having formations for operating said actuators and positioned on one side of said plate portion, said handle portion extending through an aperture in said plate portion to another side thereof.

5. The combination of claim 4 in which the means defining said discreet positions for said selector includes a retaining means mounting said selector to said mounting member.

6. The combination of claim 5 in which the retaining means is mounted beyond said another side of said plate portion.

7. The combination of claim 6 in which the aperture is an elongated opening guiding said selector for linear motion, said retaining means including a biasing element urging said selector against said one side of said plate portion.

8. The combination of claim 7 in which the retaining means also includes a detent element extending across the width of said opening with the biasing element urging the ends of said detent element against the other side of said plate portion.

9. The combination of claim 8 in which the other side of the plate portion is provided with first, second, and third detent formations positioned to receive said detent element comprising other portions of the means defining said discreet positions and cooperating with said detent element to releasably retain said selector at a selected one of said discreet positions.

10. The combination of claim 9 in which the detent element comprises a pin extending through said handle portion and said biasing element is carried by said handle portion.

11. The combination of claim 1 in which there is means defining a linear motion path for movement of said selector between said positions, said second position being intermediate said first and said third positions, an enclosure wherein said interlock unit and said selector device are mounted, an operable cover for said enclosure, an operating member rotatably mounted on the outside of said cover, a crank member on the inside of said cover connected to said operating member for operation thereby, said crank member having spaced arms with oppositely flared camming formations on the sides of said arms remote from said cover, means biasing said crank to a central position where when said selector is in said second position, upon closing of said cover said crank will remain in said central position and the space between said arms will receive a handle formation of said selector.

12. The combination of claim 11 in which the handle formation is positioned with an end portion facing said cover, said end portion engaging one or the other of said oamming formations when said cover is closed at a time said selector is not in said second position whereby said operating member is rotated from said central position to a position corresponding to the position of said selector.

13. In a device of the class described having an enclosure with an openable cover and a switching handle mounted within said enclosure for linear movement between .a first position and a third position, and a second position between said first and said third positions, means for operating said handle; said means comprising an operating member rotatably mounted on the outside of said cover, a crank member on the inside of said cover connected to said operating member for operation thereby, said crank member having spaced arms with oppositely flared camming formations on the sides of said arms remote from said cover, means biasing said crank to a central position, when said handle is in said second position and said cover is closed said crank remaining in said central position with said handle disposed in the space between said arms.

14. The device of claim 13 in which closing of said cover with the handle in said first or said third positions results in one of said camming formations engaging said handle whereby said operating member is rotated from said central position to a position corresponding the position of the handle.

15. A selector device comprising a mounting member and a selector carried by said member for movement with respect thereto, means defining discreet first, second and third positions for said selector relative to said memher, said selector including a main portion having a first cam and a second cam for operating electrical switches, said member having an aperture and said selector also including a handle portion extending through said aperture in said member, said means defining said discreet positions including retaining means mounting said selector to said member.

16. The device of claim 15 in which the mounting member includes a plate portion having said aperture therethrough, said main portion positioned on one side of said plate portion, said retaining means positioned on an other side of said plate portion, said retaining means including a spring biasing said selector against said one side.

17. The device of claim 16 in which the aperture is an elongated slot for establishing a linear motion path for said selector, said retaining means also including a detent element extending across the width of said opening with the spring urging the ends of said detent element against said another side of said plate portion.

18. The device of claim 17 in which the other side of the plate portion is provided with first, second, and third detent formations positioned to receive said detent element comprising other portions of the means defining said discreet positions and coperating with said detent element to releasably retain said selector at a selected one of said discreet positions.

19. The device of claim 18 in which the detent element comprises a pin extending through said handle portion and said biasing element is carried by said handle portion.

20. The device of claim 19 in which the mounting member includes wings offset from said plate portion for mounting said device directly to an interlock unit.

21. In combination a main interlock unit, a contactor operating coil, and a selector device; said unit including a first normally open switch and a second normally closed switch serially connected and connected in series with said coil, a housing wherein said switches are disposed, first and second actuators extending externally of said housing for operating said first and second switches, respectively; said selector device comprising a mounting member, a selector carried by said member and movable with respect thereto, and means defining discrete first, second, and third positions for said selector relative to said member; means removably mounting said selector device in operative position relative to said interlock unit; said selector when in said first position operating said first actuator to close said first switch; said select-or when in said second position operating said second actuator to open said second switch, said selector and said main interlock unit having cooperating formations to prevent mounting of said selector to said interlock unit when there is a mechanical operating connection between said first switch and a contactor.

22. The combination of claim 21 in which the cooperating formations includes a first formation in said housing positioned to receive a mechanical operating connection between said first switch and a contactor, said cooperating formations includes a second formation carried by said selector and projecting into said first formation in the portion thereof to be occupied by such mechanical operating connection.

23. The combination of claim 22 in which the mechanical operating connection referred to therein comprises a member projecting from a contactor movable contact carrier into engagement with said first actuator when said operating coil is energized, said member having 8 a threaded part for removably mounting said member to a contactor without dismantling any portion of this contactor.

References Cited by the Examiner UNITED STATES PATENTS BERNARD A. GILHEANY, Primary Examiner. 

1. IN COMBINATION ON INTERLOCK UNIT, A CONTACTOR OPERATING COIL, AND A SELECTOR DEVICE; SAID UNIT INCLUDING A FIRST NORMALLY OPEN SWITCH AND A SECOND NORMALLY CLOSED SWITCH SERIALLY CONNECTED AND CONNECTED IN SERIES WITH SAID COIL, A HOUSING WHEREIN SAID SWITCHES ARE DISPOSED, FIRST AND SECOND ACTUATORS EXTENDING EXTERNALLY OF SAID HOUSING FOR OPERATING SAID FIRST AND SECOND SWITCHES, RESPECTIVELY; SAID SELECTOR DEVICE COMPRISING A MOUNTING MEMBER, A SELECTOR CARRIED BY SAID MEMBER AND MOVABLE WITH RESPECT THERETO, AND MEANS DEFINING DISCREET FIRST, SECOND, AND THIRD POSITIONS FOR SAID SELECTOR RELATIVE TO SAID MEMBER; MEANS MOVABLY MOUNTING SAID SELECTOR DEVICE IN OPERATIVE POSITION RELATIVE TO SAID INTERLOCK UNIT; SAID SELECTOR WHEN IN SAID FIRST POSITION OPERATING SAID FIRST ACTUATOR 